Assembly unit for the construction of composite lamp holders

ABSTRACT

The present invention relates to an assembly unit for the construction of composite lamp holders, each unit comprising push-in type connecting plugs and at least two matching sockets, so that several units can be fitted together in selected desired association by plugging some or all the plugs of each of a number of units into one or more of the sockets of other units comprised in said number to construct lamp holder combinations of divers kinds.

Sept. 2, 1975 United States Patent 1191 Kommern et a1.

[ 1 ASSEMBLY UNIT FOR THE 1 583,313 5/1926 Robertson......t..,...................

CQNSTRUCTION 0F COMPOSITE LAMP l.635,889 7/1927 HOLDERS 2,218,545 10/1940 Morten 3,721,814 3 1973 Ries Invent: FOREIGN PATENTS OR APPLICATIONS [75] Hans Nagel Kommern; Werner 339/159 C 339/92 R France 240/10 R Stoff, both of Cologne, Germany [73] Assignee: Nagel KG, Wesseling, Germany [22] Filed: Apr. 24, 1973 [21] Appl. No.: 354,085

Primary ExaminerRoy D. Frazier Assistant ExaminerLawrence J. Staab Foreign Application Priority Data Attorney, Agent, or F irmMichael S. Striker 57 ABSTRACT The present invention relates to an assembly unit for [52] US. 339/158; 339/92 R the construction of composite a holders each unit [51] Int. HOlR 13/50; HOlR' 13/54 comprising push in type connecting plugs and at least [58] held of 240/10 R; 339/25 154462 two matching sockets, so that several units can be fit- 339/ 167-171 75 92 R ted together in selected desired association by plugging some or all the plugs of each of a number of units [56] References C'ted into one or more of the sockets of other units com- UNITED STATES PATENTS prised in said number to construct lamp holder combinations of divers kinds.

240/73 R Bouchery.........,.......1.......... 339/161 7 16 Drawmg Flgures 776,326 11/1904 Hubbell 881,284 3/1908 Atkinson.... 1,257,973 3/1918 PATENTEU SEP I975 SHEET 1 OF 8 FIG. 1

PATENTEUSEP 2 I 3.902.781

sumuuqa FIG. 5 FIG. 5 FIG. '7

PATENTEDSEP 2191s SHEET 5 [IF 8 PATENTED SEP 1975 SHEET 6 [IF 8 FIGJOQ PATENTED EP 2191s sum 7 o a FIG."

ASSEMBLY UNIT FOR THE CONSTRUCTION OF COMPOSITE LAMP HOLDERS The present invention relates to an assembly unit for the construction of composite lamp holders, each unit comprising push-in type connecting plugs and at least two matching sockets, so that several units can be fitted together in desired association by plugging some or all the plugs of each of a number of units into one or more of the sockets of other units comprised in said number to construct lamp holder combinations of divers kinds.

Assembly units containing at least three plug-andsocket type connectors for building up candelabra are already known. However, these are merely composite candlesticks for wax of stearine candles or tapers.

The object of the present invention if the provision of assembly units for the assembly of lamp holders or electroliers which use electric lamps as light sources and which do not, as in Christmas tree fairy lamp decorations and so forth, require the provision of external electrical wiring for electrically connecting together the assembly units in any desired combination for the construction of a diversity of kinds of lamp holder.

According to the invention this object is achieved by providing the sockets and plugs of each unit with electrical contact-making elements which are screened and insulated by insulating members and, in a first embodiment of the invention, by adapting these electrical contact-making elements so that assembly units can be plugged together or electrical imitation candles or like decorative fittings can be plugged into the units.

By virtue of the insulation and screening of the contact-making elements in the sockets and in plugs which are disposed coaxially therewith, it is readily possible to use such assembly units singly, for instance if they incorporate three connector elements, for use as electrical candelabras to be provided with a corresponding number of electrical imitation candles, or alternatively to construct major lamp holder designs by fitting together several such assembly units.

In a preferred embodiment of the invention the electrical contact-making elements are of the two-pole socket type, a contact-making pin being located in the common axis of the socket and plug of each connector element, said pin being electrically connected to a contact-making sleeve which is coaxial therewith at the other end of the connector element and the pin and the sleeve being concentrically surrounded by similarly interfitting contact-making sleeves facing opposite directions at opposite ends of the connector element, whereas insulating skirts which project beyond the ends of the contact-making elements are fixed at one end of the connector element and spring biassed so to project at the other end. The diameters of the annular end faces of the spring biassed insulating skirts are so chosen that they abut the annular end faces of the fixed insulating skirts when such a plug socket of two units are fitted together.

The invention thus provides a coaxial plug-andsocket connection in which the poles cannot be accidentally wrongly connected and the contact elements themselves are enclosed all-around by insulating elements. By fitting together a plurality of plugs and sockets complete electrical connections through the connectors will be established at the same time.

The assembly units may be built to comprise say three sets of electrical contact-making elements disposed at equidistant intervals of around a central screw or bayonet type lamp socket and the entire arrangement including the wiring may be so enclosed in insulating material that a self-contained electrical component results which incorporates all the currentcarrying elements. This electrical component may then be embedded in a divided two-part zinc pressure casting to form the body of the assembly unit, the two parts being joined by the application of pressure.

Since the desired construction of electrical lamp holders can be built up simply by fitting together such assembly units from the bottom upwards in any desired configurations, it is further proposed in another embodiment of the invention so to contrive the assembly units that they can be fitted together alternately in the upward or downward direction, i.e., that starting from an assembly unit that has already been secured at some elevation the next assembly unit can be attached thereto upside down in the downward direction and then a further unit again in the upright position and so forth as may be desired. 7

According to another feature of the invention this is achieved in that the sockets of each assembly unit are located back-to-back, pointing upwards and downwards, and laterally offset from a central plug and that each plug is provided with a releasable fastening means for coupling the same to one of the sockets or to the plug of another like assembly unit.

Thus designed assembly units offer a wide diversity of constructional possibilities, because without any change in external geometry and without additional aids they can be placed on a bearing surface, such as a floor, a table top, or the like as a lamp standard, or attached to a vertical wall or a ceiling to serve as a wall or ceiling lighting fitting. Moreover, starting with one or more assembly units to form a base any desired lamp holder construction can be assembled, i.e., begining from a table top, from a vertical wall or from a ceiling and proceeding upwards and sideways, or conversely downwards and sideways, or as may be desired.

In a preferred embodiment of the invention the assembly unit may be trumpet-bell shaped, the sockets being arranged to pass through the body of the trumpet-bell in back-to-back paired disposition with their axes parallel to, and symmetrically offset from, the vertical centre axis of the unit in which the plug forms a central tubular stem.

In order to permit the assembly units to be combined with other assembly units in as many ways as possible, the fastening means may comprise an anchoring pin which is releasably insertable into the plug, projects from the bottom end of the plug, and carries a fixing member, such as a nut, a head or the like forming a nut, adapted to bear against an abutting face on a socket.

By providing the plug with at least two contact pins parallel to the anchoring pin and by providing in each socket at least four sheaths into which the contact pins fit, it is possible to connect each assembly unit to another assembly unit in at least two relatively perpendicular positions by fitting the plug into either of the two pairs of sheaths provided in each of the two pairs of back-to-back sockets on either side of the central plug of another unit. Lamp holders can thus be constructed by building in the upward or downward directions in two or three dimensional configurations sideways as well as backwards and forwards.

Other details and advantages of the invention will be understood from the following particular description of preferred embodiments illustrated by way of example in the accompanying drawings in which FIG. 1 is a side elevation of an assembly unit according to the invention comprising two plug and socket elements fitted with electrical imitation candles,

FIG. 2 is a side elevation of a different assembly unit, comprising three plug and socket elements and a central lamp socket.

FIG. 3 is a top plan view of the unit according to FIG.

FIG. 4 is a section of part of an assembly unit, taken on the line IV IV in FIG. 3.

FIG. 5 and 6 are two different side elevations of an an assembly unit,

FIG. 7 is an imitation candle which can be fitted into an assembly unit according to the invention, whereas FIG. 8 illustrates the construction of an electrolier or lamp holder assembly form a number of modified assembly units,

FIG. 9 is a top view of the electrolier according to FIG. 8,

FIG. 10, 10a 10b are an exploded view in a section taken on the line X -X in FIG. 11 of an assembly unit as used in the preceding construction,

FIG. 11 is a horizontal section seen from above, taken on the line XI X1 in FIG. 10,

FIG. 12 is a fragmentary exploded view in a section taken on the line XII XII of the unit in FIG. 11,

FIG. 13 is a diagrammatic representation of the electrical contact-making elements in such a unit indicated in the form ofa side elevational chain line contour, and

FIG. 14 is an elevational section of an extension piece for assembly units according to the invention.

An assembly unit 1 according to the invention, preferably in the form of a zinc pressure casting, comprises, as illustrated in FIGS. 1, 2 and 3, connectors 2 for interfitting the units, such as plugs 4 and sockets 3 which are firmly interconnected by webs 5. The assembly unit shown in FIG. 1 comprises only two connectors 2, each consisting of a socket 3 and coaxial therewith, a plug 4 whereas the assembly unit shown in FIGS. 2 and 3 comprises three connectors 2 so that a number of such units can be assembled to create combinations and constructions of lighting fittings and lamp holders of divers kinds.

If desired, assembly units according to the invention might also comprise more than three connectors in suitable configurations, particularly in conjunction with additional decorative elements such as fancy flower pots, trays and similar items. However, apart from such special embodiments, assembly units comprising three connectors have proved to be most versatile since they will individually serve as lamp holders and can also be assembled into many aesthetically pleasing combinations.

Irrespectively of the number of connectors 2 and of their disposition in a single assembly unit, the sockets 3 and the coaxial plugs 4 in each assembly unit 1 contain electric contact-making elements 6, 7 which are illustrated in greater detail in FIG. 4. These electric contact-making elements 6 and 7 preferably form twopole pin and socket contacts so arranged that their protectively screened contact elements can be used either for connecting two assembly units 1 together or for plugging in electrical imitation candles 8 and the like.

For this purpose the sleeve-shaped socket 3 and the plug 4 of each connector 2 comprise a contact pin 9 at one end of the connector which is associated at the other end with a coaxially disposed contact sleeve 9a. Moreover, the contact pin 9 and the contact sleeve 9a are both concentrically surrounded by two similarly interfitting, likewise interconnected outer contact sleeves 10, 10a at opposite ends of the connector 2.

In an embodiment of the contact-making elements 6 and 7 which is particularly advantageous from both the electrical and mechanical points of view the contact pin 9 and the contact sleeves 9a, 10 and 10a are attached to an insulating body 11 which has upwardly and downwardly extending insulating skirts 11a, llb, 11c and 11d which insulate the contact-making elements from each other and prevent accidental outside contact with them. The contact pin 9 and the contact sleeve 10 surrounding the same are also embraced by two concentric insulating skirts 12a, 12b which are displaceable against the resistance of coil springs 13a, 13b from a lower position they are shown in FIG. 4 to occupy on the right of the contact pin 9 into an upper position shown on the left hand side of the pin. The annular end faces 12a and 12b of the two movable insulating skirts 12a and 12b match the annular end faces 11c, l ld of the two fixed insulating skirts 11c and 11d at the other end of the connector. When the contactmaking elements 6, 7 of two units 1 are plugged together the movable insulating skirts 12a, 12b yield upwards against the resistance of their coil springs 13a, 13b, thus permitting the contact pin 9 and the contact sleeve 9a on the one hand and the contact sleeves l0 and 10 a of the two-pole contact-making devices on the other hand to establish an electrical connection.

In order to facilitate the assembly of two units the outer of the two movable insulating skirts 12a and 12b may preferably be divided into complementary segments by the provision of two or more longitudinal slits. Furthermore, the two upper fixed insulating skirts 11c and 11d and the two lower movable insulating skirts 12a and 12b axially project beyond the ends of the contact pin 9 and of the contact sleeves 9a, 10, 10a at each end of the connector 2. Moreover, an insulating button 14 is attached to the tip of contact pin 9 to prevent the insulating skirts 12a and 12b from being moved unless interfitting assembly units 1 are actually being plugged together. All the contact-making ele-.

ments 6, 7 of one unit are wired up in such a way that matching units 1 can be plugged together without risk of creating a short circuit.

Other lighting effects can be achieved with the aid of such assembly units 1 by providing one or more webs 5 between several push-in connectors 2 of each unit 1 with an upright lamp socket 15 of which the two terminals 15a and 15b are electrically connected to the two poles 16a, 16b of the contact-making elements 6, 7. This affords the incidental advantage of enabling such an assembly unit to be used as a mains connection by screwing a suitable electrical mains adaptor into the lamp socket 15. Alternatively the connecting web or webs 5 between the several connectors 2 may be provided with a secondlamp socket or mains adaptor l5 pointing downwards and the poles of this additional element electrically connected to the two poles of all the contact-making elements 6, 7 comprised in the unit. In such a case suitable; lamps, such as bulbs, candleshaped lamps or the like, should always be screwed into the upper lamp socket, whereas the connection to the mains should always be made from the mains adaptor underneath.

However, as a general rule, current will be supplied through a base provided with a protective earth conductor so that the interconnected units which are fitted together on this base will all be earthed by contact between their zinc castings. If desired, each base element may also be fitted with a fuse.

It will be understood from FIGS. 5 and 6 that the two contact-making sleeves 10, a are tubular members with an enlarged bottom end so contrived that the enlarged end is a push fit on the other end of a similar sleeve for the creation of electrical contact between two units 1 that are plugged together as already described. One side of the sleeve has a lug 10b which is bent outwards and which can be, wired to similar contact sleeves in the same assembly unit 1. The tubular sleeve is also provided with lateral recesses 10c for the accommodation of the insulating member 11.

FIG. 7 shows an electrical imitation candle 8 com-. prising a shaft 80 containing a contact pin 8b and a contact sleeve 80 surrounding the pin at its bottom end and having a diameter which fits into the contactmaking element 7 of an assembly unit 1 and thus establishes an electrical connection to an incandescent lamp 3d at the upper end of the shaft portion 8a.

FIGS. 8 and 9 of the drawing illustrate that assembly units 1 of modified construction to the first herein described unit can also be fitted together in many different ways for achieving composite lighting effects. The lighting assembly in FIGS. 8 and 9 is composed of six identical units 1 in which the plug ends of the two bottom units have been fitted together in mirror symmetry so that the bottom unit 1 which stands upside down serves as a base for supporting the upright unit 1 which is attached thereto. The two units are firmly connected together by a fastening device which will be later described. Starting from the second unit 1 two further units 1 have been added in a manner forming a series of steps. On the far right another unit 1 is fitted from underneath to the preceding uppermost unit 1 after the insertion of a tubular extension piece 24, so that this last unit again hangs upside down. With the insertion of a similar extension piece 24 in the upward direction yet another unit is fitted upright to the left hand side of the second unit. An incandescent lamp 25 is screwed into the centre of each of the five upper assembly units 1.

The detailed construction of these assembly units will be understood by reference to FIGS. 10 to 13. The preferred form of each unit is roughly that a trumpet-bell 26 which springs from a central plug 4 and contains in symmetrical parallel disposition on each side of its centre axis (FIG. 10) a pair of identical sockets 3 fitted back-to-back in the trumpevbell. The plug 4 has the form of a hollow sten located in the centre axis 27 of the body of the trumpet-bell 26.

It will also be understood from FIGS. 10, 10a and 10b that each unit 1 comprises a web-like supporting frame 28 which is preferably of metal construction produced by pressure casting or diecasting, and which comprises at least two pairs of sockets 3 integrally cast with the spider-like supporting arms 29 and a ring 30 connecting the arms. The supporting structure 28 is provided with a thin outer fairing 31 preferably also of metal, sheet aluminium or the like, or also of plastics, comprising a bottom portion 31a enveloping the plug 4 and covering the underside of the supporting structure 28 and an upper portion 31b forming the top of the calyx 26,' the two portions abutting in a notional horizontal centre plane 32 between the pairs of back-to-back sockets 3 and the calyx (FIG.8 and FIG.l0).

Referring to FIG. 13 the plug portion 4 contains a cylindrical insulating member 33 carrying two contact pins 34 which can be plugged into corresponding sheaths 35 indicated in dotted lines above and below an insulating member 36 inserted into each socket 3.'E'ach insulating member 36 contains at least four such sheaths 35 (FIGS. 11 and 12) for the reception of the two contact pins 34 in such manner that each unit 1 can be plugged into another unit 1 'in at least two angularly different positions which in the illustrated example differ by about the centre axis 37. The contact pins 34 are protected inside the tubular end of the plug 4. Furthermore each socket 3 contains an annular slit 3a embracing the contact sleeves 35 for the reception to a defined depth of the tubular bottom end of the plug 4.

In order to prevent relative rotation between units 1 which have been plugged together the annular slit 3a in each socket 3 contains at least one locating boss 3!; projecting upwards and one downwards and the tubular end of the plug 4 is formed with at least two corresponding locating recesses 4a in quadrature. In the illustrated embodiment there are four bosses'3b. equidistantly distributed in each annular slit 3a and they cooperate with four corresponding notches 4a in quadrature in the bottom end of the plug 4.

Further with reference to FIG. 13 the fastening means comprises a threaded pin 38 which is detachably inserted from above into a centre bore 37 in the insulating member 33 inside the plug 4. This pin 38 projects from the unit 1 beyond the bottom end of the plug 4 and its free end carries a locking member 39 which can be tightened against an abutting surface such as the end face of a socket 3. The locking member may simply be a nut which is externally shaped to comply with the general contour of the assembly unit.

In the middle of the calyx 26 of each assembly unit 1, as will also be understood from FIG. 13, there is a plug-in type socket 41 for an incandescent lamp 25, this socket being electrically connected to the contact pins 34 below and to the sockets 35 on each side by suitable wires 40.

The tubular extension piece 34 illustrated in FIG. 14

for extending the plug 4 of any unit 1 has the same external and internal diameters as the plug 4, so that two insulating members as provided in the plug, can be fitted together in its interior. The length of the extension member 24 is equal to the perpendicular distance A (FIG.10) between the bottom free end of the plug 4 and the horizontal median plane 32 dividing the pairs of back-to-back sockets in the calyx portion 26 of each unit 1. The extension piece is further provided at its upper end with two locating projections 33b and at its bottom end with two corresponding locating recesses 33a so that, as shown in FIG. 8, such an extension piece is insertable from above or from below into a socket 3 in an assembly unit 1 instead of the plug 4 of another unit 1. However, a further unit 1 can now be plugged into the free end of the extension piece. In exactly the same way as each assembly unit 1 the extension piece 24 has a central bore 37 through the insulating members 33 and a threaded fastening pin 38 of suitable length can be inserted into this bore from an assembly unit 1 until the projecting end of the pin is engageable by a locking nut 39. The extension piece 24 with the next unit 1 can thus be affixed to the pair of sockets 3 of a preceding unit 1, in the manner shown in FIGS.

We claim:

1. An assembly unit for the construction of composite lamp holders, said unit having a generally trumpetshaped body having an axis, each unit comprising at least one central plug-type electrical contact element forming a tubular stem in the axis of said body; at least two pairs of opposite socket-type elements, the sockettype elements of each pair being arranged back to back passing through said trumpet-shaped body, and said at least two pairs are disposed parallel with and symmetrically laterally offset from the axis of said body, at least one of said socket-type elements of each pair being adapted to receive a plug-type element of another like unit; and releasable fastening means for coupling said plug-type element to one of the socket-type elements of another like unit, said fastening means comprising an anchoring pin which is releasably inserted into the plug-type contact element, projecting from the bottom end of the latter, and carrying a fixing member adapted to bear against an abutting face on a socket-type element.

2. An assembly unit as defined in claim 1, and including a further central contact element in form of a socket adapted to receive a lamp aligned with and axially spaced from said plug-type element and facing away from the latter.

3. An assembly unit as defined in claim 1, wherein the plug-type contact element contains at least two contact pins parallel to the anchoring pin, and wherein each socket-type contact element contains at least four tubular sheaths for the reception of said contact pins in such a manner that each assembly unit is connectable to another like assembly unit in a selected one of at least two relatively perpendicular positions.

4. An assembly unit as defined in claim 3, wherein each socket-type contact element is provided with at least two locating bosses facing in opposite directions for cooperation with at least two corresponding recesses provided at angular intervals in the tubular end of the plug-type contact element.

5. An assembly unit as defined in claim 4, and including a supporting metal web structure incorporating at least two integrated pairs of socket-type elements, said structure being covered with a thin external fairing.

6. An assembly unit as defined in claim 5, wherein a socket for an incandescent lamp is located in the center of the trumpet-bell-shaped body, said socket being electrically connected to the contact pins of said plugtype contact element and to the laterally offset contactmaking sheath.

7. An assembly unit as defined in claim 6, and including a tubular extension piece for the plug-type contact element of each assembly unit, said extension piece having the-same external diameter as said plug-type contact element and being of a length equal to the perpendicular distance between the bottom free end of the plug-type contact element and the horizontal center plane dividing the back-to-back pairs of socket-type contact elements in the -body of the trumpet bell of each assembly unit. 

1. An assembly unit for the construction of composite lamp holders, said unit having a generally trumpet-shaped body having an axis, each unit comprising at least one central plug-type electrical contact element forming a tubular stem in the axis of said body; at least two pairs of opposite socket-type elements, the socket-type elements of each pair being arranged back to back passing through said trumpet-shaped body, and said at least two pairs are disposed parallel with and symmetrically laterally offset from the axis of said body, at least one of said sockettype elements of each pair being adapted to receive a plug-type element of another like unit; and releasable fastening means for coupling said plug-type element to one of the socket-type elements of another like unit, said fastening means comprising an anchoring pin which is releasably inserted into the plug-type contact element, projecting from the bottom end of the latter, and carrying a fixing member adapted to bear against an abutting face on a socket-type element.
 2. An assembly unit as defined in claim 1, and including a further central contact element in form of a socket adapted to receive a lamp aligned with and axially spaced from said plug-type element and facing away from the latter.
 3. An assembly unit as defined in claim 1, wherein the plug-type contact element contains at least two contact pins parallel to the anchoring pin, and wherein each socket-type contact element contains at least four tubular sheaths for the reception of said contact pins in such a manner that each assembly unit is connectable to another like assembly unit in a selected one of at least two relatively perpendicular positions.
 4. An assembly unit as defined in claim 3, wherein each socket-type contact element is provided with at least two locating bosses facing in opposite directions for cooperation with at least two corresponding recesses provided at 90* angular intervals in the tubular end of the plug-type contact element.
 5. An assembly unit as defined in claim 4, and including a supporting metal web structure incorporating at least two integrated pairs of socket-type elements, said structure being covered with a thin external fairing.
 6. An assembly unit as defined in claim 5, wherein a socket for an incandescent lamp is located in the center of the trumpet-bell-shaped body, said socket being electrically connected to the contact pins of said plug-type contact element and to the laterally offset contact-making sheath.
 7. An assembly unit as defined in claim 6, and including a tubular extension piece for the plug-type contact element of each assembly unit, said extension piece having the same external diameter as said plug-type contact element and being of a length equal to the perpendicular distance between the bottom free end of the plug-type contact element and the horizontal center plane dividing the back-to-back pairs of socket-type contact elements in the body of the trumpet bell of each assembly unit. 